Conventional aircraft typically include a variety of movable aerodynamic devices for controlling the pitch, yaw and roll of the aircraft and for altering the lift characteristics of the aircraft. For example, fixed wing aircraft may include ailerons mounted to the trailing edge of the wings for roll control of the aircraft. The wings may also include flaps or slats mounted to the leading edge of the wings and which may be deployed or deflected downwardly from the wings during certain phases of flight in order to maintain airflow over the wing at high angles of attack.
Flaps may be also mounted to the trailing edges of the wings to increase the amount of lift generated by the wings when the aircraft is moving through the air at relatively slow speeds. Trailing edge flaps are typically deflected downwardly during takeoff to increase lift and are then retracted during the cruise portion of a flight. The flaps may again be deflected downwardly during the approach and landing phases of the flight to reduce the landing speed of the aircraft.
Although generally effective for reducing the landing speed of an aircraft, the deflection of conventional flaps may produce several undesirable effects. Such undesirable effects may be attributed to gaps that are created between the side edges of the deployed flaps and the wings. For example, the flow of air around the relatively sharp side edges of a deflected flap may result in formation of vortices along the side edges. Such vortices may increase the aerodynamic drag of the flap which may reduce the aerodynamic efficiency of the wing. The vortices may also cause vibration and flutter in the flap which may have an undesirable effect on the flap actuation mechanism.
Even further, vortices that may form along the side edge of a deflected flap may generate a significant amount of noise. Although flap noise may have minimal impact when the aircraft is at high altitudes or is flying over unpopulated areas, the noise generated by deployed flaps may have a greater impact when the aircraft is near populated areas located underneath the landing pattern of an airport. In this regard, flap noise may comprise a significant portion of the overall noise generated by the aircraft during the approach and landing phases of flight when the engines are typically idling.
As can be seen, there exists a need in the art for a system and method for minimizing or eliminating gaps occurring between the side edges of a flap and a wing when the flap is deflected.